CN103228393A

CN103228393A - Joint

Info

Publication number: CN103228393A
Application number: CN2011800567632A
Authority: CN
Inventors: 石田友幸; 森口秀树; 中岛猛; 久木野晓; 万木伸一郎; 榎并晃宏; 冈村克己; 松田裕介; 佐野浩司; 小林庆三; 尾崎公洋
Original assignee: National Institute of Advanced Industrial Science and Technology AIST; Sumitomo Electric Hardmetal Corp; Sumitomo Electric Industries Ltd
Current assignee: National Institute of Advanced Industrial Science and Technology AIST; Sumitomo Electric Hardmetal Corp; Sumitomo Electric Industries Ltd
Priority date: 2010-11-26
Filing date: 2011-11-22
Publication date: 2013-07-31
Anticipated expiration: 2031-11-22
Also published as: JP5552543B2; WO2012070563A1; JPWO2012070563A1; CN103228393B; EP2644307A4; KR101425330B1; US20130236240A1; EP2644307A1; KR20140002663A; US9308707B2; EP2644307B1

Abstract

This joint has a cemented carbide sintered compact as a first material being joined (1) and a cBN sintered compact as a second material being joined (2). The joint is characterized by the first material being joined (1) and the second material being joined (2) via a joining material (3) containing titanium (Ti) disposed therebetween and a titanium nitride (TiN) compound layer with a thickness of 10-300 nm formed in the interface between the second material being joined (2) and the joining material (3).

Description

Conjugant

Technical field

The present invention relates to conjugant, relate in particular to the conjugant that is applicable to cutting element.

Background technology

Traditionally, produced the cutting element that the tip has high hardness material, this high hardness material through soldered joint to its tip, this cutting element be represented as cubic boron nitride (cBN) cutting element, this cutting element has been used to cut special steel and other various types of machining.

Particularly, for example, made and sold instrument with carbide alloy and cBN, wherein this carbide alloy and cBN (for example are bonded together through soldering, the IGETALLOY cutting element of Sumitomo Electric Hardmetal Co., Ltd. issue (' the 07-'08 catalogue), in October, 2006, L4 page or leaf, Coated SUMIBORON Series(non-patent literature 1)).Perhaps, proposed by soldering the PCD(sintered diamond) or cBN and pottery, cermet or carbide alloy be joined together the conjugant (for example, the spy opens 2002-036008 communique (patent documentation 1) and special permission No. 3549424 communiques (spy opens flat 11-320218 communique (patent documentation 2))) that forms.In addition, also proposed by adopting the Cu solder to carry out soldering so that carbide alloy or cermet and high-speed steel etc. are engaged the cutting element (for example, the spy opens flat 11-294058 communique (patent documentation 3)) that forms.

Especially in recent years, the cutting element that carbide alloy and cBN are bonded together causes concern especially.

Reference listing

Patent documentation

Patent documentation 1: the spy opens the 2002-036008 communique

Patent documentation 2: Japan Patent No.3549424(spy opens flat 11-320218 communique)

Patent documentation 3: the spy opens flat 11-294058 communique

Non-patent literature

The IGETALLOY cutting element of non-patent literature 1:Sumitomo Electric Hardmetal Co., Ltd. issue (' the 07-'08 catalogue), in October, 2006, L4 page or leaf, Coated SUMIBORON Series

Summary of the invention

Technical problem

Yet, can not think that the conjugant that obtains by above-mentioned conventional method has enough big bond strength, people need a kind of conjugant with bigger bond strength, particularly carbide alloy and cBN firm engagement conjugant together.

The scheme of dealing with problems

In order to address the above problem, the inventor has carried out various experiments and deep research, found that, usually when contain in the grafting material be useful on cemented carbide sintered body and cBN sintered body in conjunction with the Ti of phase component the time, then when engaging, Ti is diffused in described cemented carbide sintered body and the cBN sintered body as a kind of chemical element, and described sintered body is bonded together securely, promptly can obtain the high conjugant of bond strength.

Have been found that in addition in this joint, the product or the TiN compound layer of the nitrogen component that has generated Ti and cBN sintered body at the interface between grafting material and cBN sintered body, and the thickness of this TiN compound layer is relevant with bond strength.

More specifically, heat time heating time is longer and contain the thickness that more substantial Ti can increase the TiN compound layer, therefore under the synergy of TiN compound layer for the excellent wetability of cBN sintered body, provides higher bond strength.Yet, when the TiN compound layer surpasses certain thickness, the fragility of TiN compound layer will have bigger influence to bond strength, if and the TiN compound layer that forms is blocked up, more specifically, if form the TiN compound layer that thickness surpasses 300 nanometers (nm), then the TiN compound layer ruptures easily and big bond strength can not be provided.Be more preferably below the 100nm, because this thickness helps the bond strength that provides big.In addition, described TiN compound can be granular crystal, column crystal, amorphous state or any crystalline state.

On the contrary, have been found that, introducing amount short when time of heating or Ti is less and when therefore making the TiN compound layer thickness too small, more specifically, when the TiN compound layer that forms during less than 10nm, Ti is as the diffusion of chemical element in material to be joined and insufficient, and can not form the TiN compound layer on whole composition surface, thereby tend on less area, form the TiN compound layer, therefore can not provide big bond strength.It should be noted that the TiN compound layer can contain a small amount of other components except that Ti and N.Such component can comprise chemical element that constitutes cBN and carbide alloy and the chemical element that constitutes grafting material.

The present invention is based on above-mentioned discovery, and the present invention is a kind of like this combination, it has as first and is engaged the cemented carbide sintered body of material and as the second cBN sintered body that is engaged material, wherein: described first is engaged material and described second is engaged material and is bonded together by grafting material, and wherein this grafting material is arranged on described first and is engaged material and described second and is engaged between the material and contains titanium (Ti); And be engaged described second and form the titanium nitride that thickness is 10nm-300nm (TiN) compound layer at the interface between material and the described grafting material.

Therefore the present invention can provide the conjugant that has high bond strength as mentioned above between cemented carbide sintered body and cBN sintered body, and cutting element with high bond strength etc. can be provided.

As mentioned above, set titanium nitride (TiN) compound layer of the present invention also contains such compound, this compound contains a spot of other chemical elements except that Ti and N, and the content range of these other chemical elements drops in the scope that can not depart from purport of the present invention.

When engaging by heating, the cBN sintered body is thermo-labile and can at high temperature decompose, so the thermal decomposition at short notice of cBN sintered body.Therefore, preferably carry out the short time heating.

Concrete preferred mode of heating be conduction time one minute with interior resistance heated, more preferably in 30 seconds, in this case, first temperature that is engaged material or cemented carbide sintered body is preferably about 1000 ℃-1300 ℃.

Preferred fusing point is equal to or less than 1000 ℃ grafting material, and this is because this grafting material can prevent cBN Sintered Quality deterioration, and is convenient to the THICKNESS CONTROL of TiN compound layer within the limits prescribed.

If the fusing point of grafting material is equal to or higher than 1000 ℃, the TiN compound layer that then obtains specific thickness needs longer heat time heating time or higher heating-up temperature.Yet the heating of longer time causes the deterioration of cBN quality easily, and heating may cause excessive and cemented carbide sintered body distortion of the thickness of TiN compound layer or the like under higher temperature.

Preferably in heating, longitudinally suppress with horizontal both direction.

By longitudinally suppressing with horizontal both direction, the cBN sintered body can engage at the place, fixed position with respect to cemented carbide base material, therefore can accurately locate.With compare to suppressing along folk prescription, grinding amount after this allows and engages reduces, and in addition, the displacement and the stock removal of cBN sintered body is designed to minimum demand, this makes that the size of employed cBN sintered body is littler, and the use amount of expensive cBN sintered body is reduced.

In addition, preferably under controlled-load, longitudinally and laterally suppress, this is because of the thickness ratio of knitting layer THICKNESS CONTROL for stipulating that helps like this bottom surface and place, the back side.In addition, not only depend on wetability, can also increase the contact area between material to be joined and grafting material, therefore, can increase the area that they contact with each other at short notice, this is preferred.Improperly will mainly not locate to disadvantageously form the gap overleaf, and width is equal to or greater than the gap of 0.5mm and especially can causes bond strength to reduce along laterally suppressing or suppress.In addition, even without forming the gap, do not suppress also can cause being easy in knitting layer, stay bubble, and expectability activity chemistry element does not spread by compacting.In addition, if heat time heating time is short, then the not enough grafting material that can stop of wetability is fully sent out between material to be joined, and the bonding area of these materials is tending towards reducing as a result, causes bond strength to reduce.

In addition, when on cemented carbide base material, applying too small compacting load and carrying out resistance heated simultaneously, can cause the contact resistance between cemented carbide sintered body and the electrode to increase, and similar problem such as the obstructed or discharge of electric current may take place.When carrying out resistance heated, preferably apply the pressure of 0.1MPa-200MPa.

For the cBN sintered body by will comprising cobalt metallic bonds such as (Co) and/or the sintered body with the cBN that surpasses 70% high cBN content join the instrument that obtains on the carbide alloy to as material to be joined, it has following problems: when engaging when heating for a long time in process more than 1000 ℃, the cBN sintered body can ftracture, and this causes being difficult to obtain gratifying joint.

It is believed that this may be because there is significant difference in the thermal coefficient of expansion between cBN and the metallic bond, thereby when they were heated to more than 1000 ℃, the volumetric expansion of metallic bond was big, thereby cBN sintered body cracking; Perhaps surpass 70% cBN content if the cBN sintered body has, then it is with bigger as the thermal expansion coefficient difference between the carbide alloy of base material, thereby the cooling period behind their joints, and the cBN sintered body can ftracture.In addition, this also may be because the metallic bond in the cBN sintered body is forming liquid phase more than 1000 ℃, thereby makes cBN sintered body cracking.

In order to prevent this quality deterioration of cBN sintered body, the arrangement and the electrifying method of good cBN sintered body of decision design and grafting material make that during resistance heated, cemented carbide sintered body more preferably generates heat than cBN sintered body.

Particularly, this comprises (for example) electrode and the different material of electrode use that contacts cemented carbide sintered body for contact cBN sintered body.The electrode that is formed by different materials makes the electric current of different amounts by described sintered body, to control the heating of each sintered body respectively.In addition, can carry out the resistance heated more concentrated to cemented carbide sintered body and come indirect cBN sintered body than cBN sintered body.

By setting electrical path like this, cemented carbide sintered body can more preferably be heated than cBN sintered body, and this is preferred.Though no longer the cBN sintered body is heated exceeding under the high temperature of needs, but can be at high temperature to carrying out the short time heating near the grafting material, form firm joint thus, in addition, can make full use of the characteristics such as high rigidity of cBN sintered body, and can not cause the quality badnesses such as thermal degradation, decomposition and cracking of cBN sintered body.

In addition, in the present invention, grafting material preferably contains one or more in selected among zirconium (Zr), cobalt (Co), nickel (Ni), silver (Ag) and the copper (Cu).

In the present invention, when grafting material is formed by the alloy that contains Ti as mentioned above, can obtain the higher conjugant of bond strength, in addition, usually as the Co and the Ni in conjunction with phase component of cemented carbide sintered body and cBN sintered body, perhaps Ag, Cu and Zr show the excellent wetability for the cBN sintered body.

This grafting material can be including (for example) Ag-Ti alloy, Cu-Ti alloy, Ni-Ti alloy, Co-Ti alloy and solid solution thereof, for example Cu-Ti-Zr alloy, Ag-Cu-Ti alloy, Cu-Ni-Ti alloy and Cu-Ni-Zr-Ti alloy etc. also have (for example) their intermetallic compound etc.It should be noted that and also can comprise other components that in cemented carbide base material or cBN, contained on a small quantity, for example W, Cr, Ta or Nb or the like.For example, can comprise Cu-Cr-Al-Ti alloy etc.

Intermetallic compound can just be included in the grafting material at first.In addition, the chemical element that constitutes intermetallic compound can be included in the grafting material with different states, and described intermetallic compound can form by reaction after engaging.When forming intermetallic compound by reaction, reaction heat can be used to engage, and therefore, it is more effective for engaging to form intermetallic compound by reaction.

In addition, in the present invention preferably, when grafting material is made of titanium (Ti), zirconium (Zr), copper (Cu) and nickel (Ni), the ratio that contains of representing Ti, Zr and Cu with x volume %, and represent that with (100-x) volume % the ratio that contains of Ni, grafting material contain Zr and (0.3-0.7) Cu of x volume % of Ti, (0.1-0.4) x volume % of (0.1-0.4) x volume %.

As mentioned above, Ni be used as cemented carbide sintered body and cBN sintered body in conjunction with phase component, Cu and Zr show the excellent wetability for the cBN sintered body, use the grafting material contain these materials can provide bond strength higher conjugant.

The inventor has carried out various experiments, find that the ratio table that always contains of Ti, Zr and Cu is shown x volume % in grafting material, and the ratio table that contains of Ni is shown (100-x) volume %, and when grafting material contains Cu, the Zr of ratio as implied above and Ti, help to make this grafting material to have gratifying fusing point and gratifying wetability, and make that joint is stronger.It should be noted that in the above description for example, expression formula " (0.1-0.4) x volume % " expression contains ratio (volume %) in the scope of 0.1x to 0.4x.

In addition, in the present invention, the ratio that contains of nickel (Ni) is equal to or less than 70 volume % in the preferred grafting material.

As mentioned above, the grafting material that contains Ni makes conjugant have higher bond strength, wherein Ni be used as cemented carbide sintered body and cBN sintered body in conjunction with phase component.Yet when the containing ratio and surpass 70 volume % of Ni in the grafting material, the content of Ti will reduce relatively in the grafting material, thereby will be difficult to obtain to have the TiN compound layer of aforesaid suitable thickness, thereby be not preferred.

In addition, in the present invention, the back side place that preferably is engaged material in second bottom surface and second that is engaged material makes second to be engaged material and first and to be engaged material and to engage, and the knitting layer thickness located of the back side is located the thickness of knitting layer greater than the bottom surface.

In cutting, particularly intermittent cutting, when the cutting element contact workpiece, the cutting edge of this instrument is impacted, and has alleviated this impact effectively as the grafting material of softer relatively layer.Yet, in the grafting material near a side of bottom surface easily under the effect of load that produces by cutting and heat and cause plastic deformation, thereby chipping resistance is reduced and machining accuracy reduces.The inventor finds, longitudinally and laterally suitably suppresses the knitting layer thickness that can make the place, the bottom surface knitting layer thickness less than place, the back side, thereby the conjugant that also has high chipping resistance when keeping machining accuracy is provided.

Usually, first is engaged material or cemented carbide sintered body forms by press molding, therefore, it with second be engaged the demoulding angle that has inclination on the back side facing surfaces of material.

Therefore, be engaged material and second with first and be engaged match materials together the time, tend to locate overleaf to produce the gap, and if grafting material (or insert material) just be dispersed throughout the bottom surface, then will produce space (or gap), and may can not get sufficient joint.Therefore, preferably, described grafting material also is used to engage the back side.

The invention provides the knitting layer of place, back side thickness greater than place, bottom surface thickness.This helps to reduce space (or gap), therefore obtains sufficient joint strength.

In addition, in the present invention, when the thickness that is expressed as the knitting layer at a and place, bottom surface when the thickness of the knitting layer at back side place was expressed as b, b was 1 μ m-50 μ m and satisfies 1＜a/b＜20.

The inventor has been found that, near the knitting layer thickness of bottom surface be 1 μ m-50 μ m, more preferably 1 this thickness of μ m-20 μ m(is less than the thickness of general vacuum brazing conjugant) above-mentioned conjugant be not easy to take place plastic deformation, and be easy to keep high manufacturing accuracy.In addition, the inventor also finds, the ratio (being a/b) of the thickness a of the knitting layer at place, the back side and the thickness b of the knitting layer at place, bottom surface is controlled at the chipping resistance that can make in the prescribed limit that the conjugant that generated keeps high manufacturing accuracy and has excellence.

More specifically, if the thickness of the knitting layer at place, bottom surface is excessive, then it is easy to take place plastic deformation at the cutting test period.In addition, if a/b is too small, if promptly the thickness of the knitting layer at place, the back side is too small than the knitting layer thickness at place, bottom surface, then knitting layer can't relax impact internally, and the chipping resistance that is difficult to effectively be improved.On the contrary, the inventor finds, if a/b is excessive, if promptly the thickness of the knitting layer at place, the back side is excessive than the thickness of the knitting layer at place, bottom surface, even it seems so in appearance as very close to each other, but the inner gapped possibility increase of knitting layer, thereby cause bond strength to reduce.Preferred 1＜a/b＜20, more preferably 2＜a/b＜15.At this moment, the thickness of the knitting layer at place, the preferred back side is 5 μ m-200 μ m, 5 μ m-100 μ m more preferably, and this is because this makes that knitting layer is not easy to have the internal clearance.About the joint Thickness Control for place, the back side and place, bottom surface that the present invention carried out, conventional method for welding is difficult to accomplish.

As mentioned above, in the present invention, a kind of like this instrument can be provided, and it can make full use of the performances such as high rigidity of cBN sintered body with high bond strength, can not cause the quality badness (thermal degradation, decomposition, cracking etc.) as the cBN sintered body of high pressure stable type material simultaneously.Particularly, because instrument of the present invention is suitable to wear resistant tools, mining and instruments such as earthworking implement and cutting element, so instrument of the present invention is preferred.

Beneficial effect of the present invention

The present invention can provide a kind of conjugant, and the bond strength of this conjugant is higher than the bond strength that conventional method obtains, and cutting element of high bond strength etc. can be provided.

Description of drawings

Fig. 1 (a) and 1 (b) are respectively the schematic side elevation and the plane of conjugant in the embodiment of the present invention.

Fig. 2 is the concept map that a kind of step mode when engaging by resistance heated and compacting is shown.

Fig. 3 illustrates thermometric side view.

Fig. 4 is the side view that ionization meter is shown.

The specific embodiment

Below with reference to the accompanying drawings embodiments of the present invention are described.

1. the formation of conjugant

Fig. 1 (a) and 1 (b) are respectively the schematic side elevation and the plane of conjugant in the embodiment of the present invention.Among Fig. 1, conjugant comprises by what cemented carbide sintered body formed and first is engaged material 1, second is engaged material 2 and is arranged on first and be engaged the grafting material 3 that material 1 and second is engaged between the material 2 and contains Ti by what the cBN sintered body formed, and is engaged second and is formed with the TiN compound layer (not shown) that thickness is 10nm-300nm at the interface between material 2 and the grafting material 3.

By resistance heated and the method that engages of compacting

At first, describe with reference to 2 pairs of methods that engage by resistance heated and compacting of figure.Fig. 2 is the concept map that illustrates by resistance heated and suppress a kind of step mode when engaging.The horizontal pressed material 36 that Fig. 2 comprises electrode 34, cuts apart electrode 35 and formed by aluminium oxide etc.

In Fig. 2, to cut apart electrode 35 and second and be engaged material 2 and contact, electrode 34 and first is engaged material 1 and contacts.By to electrode 34 with cut apart electrode 35 and use different materials, can change their electric conductivity and thermal conductivity.In addition, can be engaged to first respectively and expect that material 1 and second is engaged material 2 and applies different electric currents, and can significantly change the temperature of described material.

This makes to win and is engaged material 1 to the second and is engaged material 2 and more preferably generates heat, and can prevent thermo-labile and at short notice thermal degradation second be engaged material 2(or cBN sintered body) thermal degradation takes place.

In addition, by independently each electrode being suppressed, can control accurately and put on first and be engaged material 1 and put on second pressure that is engaged material 2.Therefore, be engaged to apply on the material 2 to suppress second along horizontal stroke side by horizontal pressed material 36 and load, and under this compacting load, suppress in the mode of optimum balance, thereby make first to be engaged material 1 and to have best contact resistance, this makes grafting material 3(or knitting layer) have an optimum thickness.

Power on condition

Power on condition is engaged material that material 1, second is engaged material 2 and grafting material 3 according to employed first and waits rightly and determine.Preferably, the time of switching on is in one minute, particularly in about 30 seconds, be engaged material 1 and second and be engaged near thickization of particle in other parts beyond the part material deformation of material 2 or fusion and the grafting material 3 to avoid causing first.

Form/the mode of grafting material

Form/mode as the grafting material 3 that is used for engaging by resistance heated and compacting, can adopt by plating method or physical vaporous deposition and be engaged the method that material 1 and/or second surface that is engaged material 2 apply, and the grafting material of Powdered, paper tinsel shape or pasty state is applied to first is engaged the lip-deep method that material 1 and/or second is engaged material 2 first.For bond strength stable, especially preferably being engaged material 1 and second by plating method or physical vaporous deposition to first is engaged the method that material 2 applies, this is because described method is convenient to be engaged the operation of

material

1 and 2 after being engaged

material

1 and 2 with grafting material 3 coatings, therefore in the automation of engagement step, be favourable, and be convenient to control the thickness of coat film.

Compacting

Resistance heated and compacting can make grafting material 3 deform, and have strengthened the adherence between grafting material 3 and material to be joined 1 and 2, and have promoted the diffusion of chemical element.Therefore, can significantly improve bond strength.Particularly, when conjugant of the present invention being applied to cutting element (for example cutting tip), be engaged composition surface directed in orthogonal direction and the horizontal direction both direction that material 1 and second is engaged material 2 as first of base material, and be necessary on this both direction, to engage securely first and be engaged material 1 and second and be engaged material 2.In this case, as mentioned above, preferably suppress along this both direction.

Compacting load is too small to be unfavorable, because this compacting load can cause electrode and contact resistance increase that is engaged by first, second between

material

1 and 2, and electric current can not flow through or can discharge.The compacting load is excessive also to be unfavorable, because this compacting load can cause the distortion of cemented carbide sintered body.Under situation of the present invention, for being engaged material 1, the compacting of 0.1MPa to 200MPa load suits, yet for material 2 to be joined, 0.01MPa-50MPa suits.

Atmosphere

First is engaged that material 1, second is engaged material 2 and grafting material 3 all comprises metal, therefore preferably in vacuum, inert gas or reducing atmosphere these materials is bonded together.Though vacuum is not particularly limited, expectation vacuum is higher than the 13.3Pa(0.1 holder).Inert gas can comprise the mixture of argon gas, helium, nitrogen or these gases.Reducing atmosphere can comprise the gas atmosphere that small scale gaseous hydrogen wherein mixes with above-mentioned inert gas, provides reducing atmosphere near maybe can placing grafting material 3 by graphite that will heating, or the like.

Mode by electric current

As the form of the electric current that passes through, if can making to win, electric current is engaged that material 1, second is engaged material 2 and grafting material 3 is heated to suitable temperature, then direct current and alternating current all can use.Particularly and since pulse direct current can change current peak and the pulse On/Off between ratio, therefore can the transient heating composition surface and can make first to be engaged the bulk temperature control range that material 1 and second is engaged material 2 and to broaden.Therefore, pulse direct current is effective aspect joint.

Set the thickness of grafting material

Below with reference to Fig. 1 the thickness of grafting material 3 is described.Can set the thickness of grafting material 3 like this, the thickness a that makes close back side 2b is greater than the thickness b near bottom surface 2a, preferred 1＜a/b＜20, to reach strong chipping resistance and to keep high manufacturing accuracy, in addition, reduce the space that the back side (locating to be easy to form the space overleaf) is located, constant high bond strength is provided thus.

Embodiment

1. making conjugant

Use each grafting material 3 that shows in the table 1, make the conjugant of embodiment 1-23 and comparative example 1-7 according to each engaging condition.

(1) thickness of TiN compound layer

Referring to table 1(" compound layer thickness " row).

(2) first to be engaged material 1(all identical in embodiment and comparative example)

Material: a part has the cemented carbide sintered body (substrate metal) of countersunk

Shape: drift angle: 90 °, inscribed circle: 12.7mm, thickness: 4.76mm, R:0.8mm(JIS:SNGN120408)

(3) second to be engaged material 2(all identical in embodiment and comparative example)

Material: cBN (insert) (cBN content: 90%)

Shape: 2mm * 1mm, and thickness is 1.2mm

(4) grafting material (forming and state), heating means and engaging condition

Referring to table 1.In table 1, the composition of the grafting material that has engaged is shown in " composition of grafting material " tabulation, and it be the result of EPMA method research, and this composition is consistent with the composition as the grafting material 3 of parent material.Be provided with first and be engaged material and second and be engaged material, make second zone and the back side that is engaged 1mm * 1mm in the material bottom surface all contact, with this understanding described material is bonded together with first countersunk that is engaged material.In table 1, the various forms/mode of grafting material is shown in " form/mode of grafting material " tabulation.Term " powder " expression grafting material is Powdered.Term " physical vapour deposition (PVD) " expression is by carrying out described grafting material physical vapour deposition (PVD) on the material and used being engaged.Term " physical vapour deposition (PVD)+plating " expression is engaged material and second with grafting material first and is engaged and carries out physical vapour deposition (PVD) on one in the material and use this grafting material plating first to be engaged material and second being engaged another person in the material.Term " powder+plating " expression uses this grafting material to be engaged material with plating, and uses with form of powder.

It should be noted that in described heating means " energising " be meant by resistance heated and compacting and engage, and under described engaging condition, the energising duration of the pulse direct current electric current shown in " heat time heating time " expression " electric current " row.The compacting of the cemented carbide base material " load " expression puts on first pressure that is engaged material." the compacting load of cBN " expression puts on second pressure that is engaged on the material." laterally compacting load " expression is by horizontal pressed material applied pressure shown in Figure 2.In addition, in described heating means, the heating means of vacuum drying oven are used in " vacuum drying oven " expression, and are illustrated under the base material temperature shown in the table 1 and heat.In addition, in described heating means, " high frequency " expression uses high-frequency induction heating apparatus to heat.

2. assay method

(1) thickness of grafting material

After the polishing, by microscopic examination, measure bottom surface grafting material thickness (near second average thickness of exposed surface of grafting material 3 (or knitting layer) that is engaged the bottom surface of material 2) and back side grafting material thickness (close second is engaged the average thickness of exposed surface of grafting material 3 (or knitting layer) at the back side of material 2).The result is presented in the table 1.The ratio (back side grafting material thickness/bottom surface grafting material thickness) of " back/underside surface thickness than " expression back side grafting material thickness and bottom surface grafting material thickness.

(2) thickness of TiN compound layer

Joint interface is carried out after the FIB processing, utilize TEM to observe and utilize EDX and EELS carries out component analysis, to measure the thickness of TiN compound layer.Observe thereby suitably regulate enlargement ratio, obtain the thickness average value in the visual field according to the thickness of TiN compound layer.The results are shown in (referring to " thickness of compound layer " row) in the table 1.

(3) measure base material temperature

Fig. 3 is the schematic diagram that the base material temperature assay method is shown.In Fig. 3, first in the conjugant is engaged material 1 and is exposed to laser facula 44 times.

Measure near first the countersunk with radiation thermometer and be engaged material 1(or cemented carbide sintered body) temperature.Particularly, as shown in Figure 3, locating laser hot spot 44(diameter is 1mm), make the center and first of laser facula be engaged material 1(13mm ²Distance between upper surface * 5mm thickness) be 1mm and and the back side of countersunk between distance be 1mm, measure temperature with radiation thermometer.Measurement result is presented in the table 1.

(4) measure bond strength

Fig. 4 shows the measuring method of bond strength.Along conjugant being suppressed from the upside of accompanying drawing paper and the direction of downside, be engaged in the material 2 simultaneously and be engaged part that material 1 stretches out from first and apply power perpendicular to described accompanying drawing paper to second, giving grafting material 3 with shearing force, and the intensity when measuring grafting material 3 fractures is as bond strength.Measurement result is presented in the table 1.

It should be noted that in table 1 embodiment of not shown bottom surface grafting material thickness or bond strength represents that the described material that is engaged is not engaged the material joint.

3. observe

After bond strength is measured, observe the plane of disruption of embodiment and comparative example with SEM-EDX.In addition, also use its composition surface of tem observation.

Observe the plane of disruption of embodiment 3 and use its composition surface of tem observation with SEM and EDX, and it is carried out EELS analyzes, thereby what disclosed inherent fracture is not that the B that is considered to fragility is rich in layer, is the TiN compound layer, but cBN, and obtained high bond strength.On the contrary, the excessive and fracture of the TiN compound layer thickness of comparative example 7 has been found that it can not provide high bond strength.Same observation other embodiment and other comparative examples.

4. estimate

Find that from table 1 bond strength of conjugant changes along with the variation of TiN compound layer thickness, and when in described layer the scope of thickness, can have high bond strength at 10-300nm.It should be noted that the a/b of embodiment 6〉20, therefore space (or gap) is arranged overleaf, reduced bond strength thus.In addition, embodiment 18-21 satisfies such condition, promptly working as grafting material is made of titanium (Ti), zirconium (Zr), copper (Cu) and nickel (Ni), represent that with x volume % Ti, Zr and Cu's always contains ratio, and represent that with (100-x) volume % the ratio that contains of Ni, described grafting material contain Zr and (0.3-0.7) Cu of x volume % of Ti, (0.1-0.4) x volume % of (0.1-0.4) x volume %.

In addition, have been found that, embodiment 2-4(promptly heats the embodiment that has carried out 10-60 second) provide thickness suitable TiN compound layer, and do not observe the cBN thermal degradation, and embodiment 3(promptly heats the embodiment that has carried out 20 seconds) extra high bond strength can be provided.

Notice that in " grafting material composition " row of table 1, Cu, Zr, Co, Ni front each have a numerical value, it represents the percent by volume of each metal.It should be noted that the Ti front without any numerical value, expression Ti is a surplus.

5. cutting test

To under the condition among the embodiment 6-12, be used for implementing cutting test by prepared conjugant.Cutting is carried out under following condition:

The shape of instrument: CNGA120408

Cutting speed: 150m/ minute

Cutting output: 0.1mm

Feed rate: 0.1mm/rev

Cutting time: 60 minutes

Be cut material: the SCN415(dry type that four grooves are axially arranged)

The results are shown in the table 2.

Table 2

Find from table 2, to be 1-50 μ m and back/underside surface thickness surpass 1 and be equal to or less than 0.28mm less than the wear extent of each conjugant (or embodiment 7-10) of 20 than (back side knitting layer thickness/bottom surface knitting layer thickness) to bottom surface place knitting layer thickness, and have excellent abrasive.On the contrary, back/underside surface thickness is more excessive than the thickness of the back side knitting layer that surpasses 20 conjugant (or embodiment 6), so the bond strength deficiency, thereby causes uncoupling to close (disjoint).In addition, too small and back/underside surface thickness bursts apart under the effect of cutting load than the conjugant (or embodiment 11) that is lower than 1 thickness of the knitting layer at back side place than the knitting layer thickness at place, bottom surface.In addition, the knitting layer thickness that the knitting layer thickness at place, bottom surface is located than the back side is excessive and back/underside surface thickness is more softening than conjugant (or embodiment 12) knitting layer during cutting that is lower than 1, and conjugant bursts apart.Yet embodiment 10 does not seriously burst apart after cutting, examines its cutting edge, finds to have compared small breach with embodiment 7-9.

Though describe the present invention, the invention is not restricted to this based on an embodiment.Identical or be equal in the scope of the present invention and can make various modification.

List of numerals

Be engaged material at 1: the first; Be engaged material at 2: the second; 2a: bottom surface; 2b: the back side; 3: grafting material; 34: electrode; 35: cut apart electrode; 36: horizontal pressed material; 44: laser facula; A: the knitting layer thickness at place, the back side; B: the knitting layer thickness at place, bottom surface.

Claims

1. conjugant, it has as first and is engaged the cemented carbide sintered body of material (1) and as the second cBN sintered body that is engaged material (2), wherein: described first is engaged material (1) and described second is engaged material (2) and is bonded together by grafting material (3), and wherein this grafting material (3) is arranged on described first and is engaged material (1) and described second and is engaged between the material (2) and contains titanium (Ti); And be engaged described second and form the titanium nitride that thickness is 10nm-300nm (TiN) compound layer at the interface between material (2) and the described grafting material (3).

2. conjugant according to claim 1, wherein, described grafting material (3) comprises one or more in selected among zirconium (Zr), cobalt (Co), nickel (Ni), silver (Ag) and the copper (Cu).

3. conjugant according to claim 2, wherein working as described grafting material (3) is made of titanium (Ti), zirconium (Zr), copper (Cu) and nickel (Ni), represent that with x volume % Ti, Zr and Cu's always contains ratio, and represent that with (100-x) volume % the ratio that contains of Ni, described grafting material contain Zr and (0.3-0.7) Cu of x volume % of Ti, (0.1-0.4) x volume % of (0.1-0.4) x volume %.

4. conjugant according to claim 2, wherein, the ratio of contained nickel (Ni) is equal to or less than 70 volume % in the described grafting material (3).

5. conjugant according to claim 1, wherein, described second is engaged material (2) is engaged material (2) in described second bottom surface (2a) and described second that is engaged material (2) the back side (2b) locates to be engaged material (1) and to engage with described first, and the thickness of the knitting layer located greater than described bottom surface (2a) of the thickness of the described back side (2b) knitting layer of locating.

6. conjugant according to claim 5, wherein, when the thickness that the thickness of the described knitting layer of locating as the described back side (2b) is expressed as the described knitting layer that a and described bottom surface (2a) locate was expressed as b, b was 1 μ m-50 μ m, and satisfies 1＜a/b＜20.